...so i got my replacement key and tried to remove the lock nut.
As I cranked on the breaker bar, it budged a little bit but didn't look like the bolt was turning, so I took the key out to inspect it. This new key was also starting to shear/shred.
So I said screw it. Went to BMW and got 4 regular bolts. removed the remaining 3 before the key was destroyed and replaced them with the regular bolts.
To remove the final (obviously over-torqued bolt), I went to Princess auto and picked up a set of reverse threaded lock removal sockets. Less than 3 seconds with an impact wrench and the bolt was out. I see no use to these things. All a thief has to do is get a set of these reverse threaded sockets (for $20), and your wheels are gone. What's the point???
Probably the last time I'll ever use lock nuts.... what a pain in the arse.